Linear guides are used for the performance of linear movements in a multiplicity of fields, such as, for example, in mechanical engineering, in handling systems, in the construction of jigs and fixtures and in precision engineering. Linear guides can be used as modules for grabs, robots, sliding tables, supports, measuring instruments, and the like. The principle component of a linear guide is one or two guide shafts on which a guide carriage slides.
In reversal, however, the guide carriage may remain stationary and the shaft or the two shafts moved. For low-friction displacement and a high load-carrying capacity, so-called spherical bushings or linear ball bearings with several ball races are generally utilized in the guide carriage.
The relative movement between the guide shaft and the guide carriage arranged thereon can be accomplished in different ways. One manner of doing this involves ball roll spindles, with a spindle running parallel to the guide shaft and a spindle nut being arranged in the guide carriage. If the spindle is driven, the guide carriage moves accordingly.
One disadvantage with this construction, however, is that besides requiring additional space for the spindle, the mechanism cannot be supported along its length which is thereby limited.
Also well known as a means for a linear drive system are drive systems with notched belts or the like; however, such an approach also requires an increased expenditure for additional components and requires operating room. Furthermore, with the belt drive, the guide shaft cannot be completely supported, which thus has a limiting effect on the overall length.
Another structure known in the art is to arrange a toothed rack parallel to the guide shaft, which works together with a counter-element, such as a pinion, for driving the guide carriage. For this, however, additional components and increased expenditures are also necessary. Furthermore, such a linear guide is subject to limitations in its use.